2. Two copper-constantan thermocouples with 1 and 2 mm diameters are taken from ambient at 20 °C, and dipped into boiling water at 100 °C. a. Find the time constant for each TC, where Time Constant, t=mc/hA Assume: Density, p = 8500 kg/m3 Specific Heat, c = 400 J/kgK Heat transfer coefficient for the TC's is h = 400 W/m²C. b. Find the output from each thermocouple after 10 seconds in the boiling water. y = Kxo (1-e¹½) Temperature (C) 110 100 90 80 70 60 50 40 30 20 10 0 L 01 L 2 I 3 L 01 4 5 6 7 8 Time (s) I 9 10 1mm diameter 2mm diameter 11 L 12 13 14

2. Two copper-constantan thermocouples with 1 and 2 mm diameters are taken from ambient at 20 °C, and dipped into boiling water at 100 °C. a. Find the time constant for each TC, where Time Constant, t=mc/hA Assume: Density, p = 8500 kg/m3 Specific Heat, c = 400 J/kgK Heat transfer coefficient for the TC's is h = 400 W/m²C. b. Find the output from each thermocouple after 10 seconds in the boiling water. y = Kxo (1-e¹½) Temperature (C) 110 100 90 80 70 60 50 40 30 20 10 0 L 01 L 2 I 3 L 01 4 5 6 7 8 Time (s) I 9 10 1mm diameter 2mm diameter 11 L 12 13 14

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.13P

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